(CNN) - The challenge was directed at the leader of ISIS, Abu Bakr al-Baghdadi. But the impassioned message, laced with Islamic phrases, sought a much wider audience.

The statement came from Barak Barfi, a spokesman for the family of slain American journalist Steve Sotloff. Sotloff, who reported for Time and other publications, was beheaded in a video ISIS released on Tuesday.

Barfi is a research fellow at the New America Foundation, a Washington-based think tank, where he specializes in Arab and Islamic affairs. On behalf of Steven Sotloff's family, he had tried to secure the journalist's release.

On Wednesday, Barfi stood outside the Sotloff family's Miami home, with dozens of microphones and cameras thrust before him, and stepped into a fierce war of words between ISIS and the rest of the Muslim world.

"I am ready to debate you with calm preachings," Barfi told al-Baghdadi, directly addressing him in Arabic. "I have no sword in my hand and I am ready for your answer.”

Speaking briefly to CNN on Thursday, Barfi said he doesn't expect the reclusive ISIS leader to accept the invitation. But his challenge had other aims, the young scholar said.

Most of the 1.6 billion Muslims in the world have, and we're utterly certain that it condemns kidnapping young girls and selling them into slavery - no matter what you say "Allah" tells you.

According to Amnesty International, several hundred schoolgirls - both Christian and Muslim - between the ages of 16 and 18 were abducted at gunpoint on April 14 from their rooms at the Government Girls Secondary School in Chibok, Nigeria, where they had been sleeping.

The armed extremist group Boko Haram, which roughly translates to “Western Education is Sin,” claimed responsibility for these mass kidnappings and threatened to sell these young girls for as little as $12 into sex slavery or forced “marriages” to members of their group.

"I abducted your girls. I will sell them in the market, by Allah," a man claiming to be Boko Haram leader Abubakar Shekau said in a video first obtained by Agence France-Presse.

(CNN) - An angry outburst at a mosque. The posting of a suspicious YouTube video. A friendship with a shadowy imam.

Those were just some of the signs that Tamerlan Tsarnaev, accused of masterminding the Boston Marathon bombings, had adopted a virulent strain of Islam that led to the deaths of four people and injury of more than 260.

But how else can you tell that someone’s religious beliefshave crossed the line? The answer may not be as simple you think, according to scholars who study all brands of religious extremism. The line between good and evil religion is thin, they say, and it’s easy to make self-righteous assumptions.

“When it’s something we like, we say it’s commitment to an idea; when it’s something we don’t like, we say it’s blind obedience,” said Douglas Jacobsen, a theology professor at Messiah College in Pennsylvania.

Washington (CNN) - Muslim leaders in Boston and elsewhere have distanced themselves from the suspects in the Boston Marathon bombing, condemning the deadly terror attack and saying they feared reprisals against their communities.

"I don't care who or what these criminals claim to be, but I can never recognize these criminals as part of my city or my faith community," said Yusufi Vali, executive director for the Islamic Society of Boston Cultural Center, the largest mosque in the Boston area.

"All of us Bostonians want these criminals to be brought to justice immediately. I am infuriated at the criminals of these bombings for trying to rip our city apart. We will remain united and not let them change who we are as Bostonians." FULL POST

Islamabad, Pakistan (CNN) - It has been more than a month since a teenage Christian girl was charged in Pakistan under the country's blasphemy laws . Her accusers say she burned pages from the Quran, Islam's holy book. Amid twists in her case, including changed statements by witnesses, she is facing life in prison.

On Monday, CNN reported that three witnesses whose testimony could absolve the 14-year-old Rimsha Masih have changed their statements, a potential setback for her. She has denied the charges.

The case has drawn the country's complex laws about blasphemy into the spotlight. Here is a primer on those laws.

Islamabad, Pakistan (CNN) - A Christian girl accused of violating Pakistani blasphemy laws by allegedly burning pages containing texts from the Quran will have to wait at least another two weeks to learn her fate after a court ordered a stay of proceedings in her case Monday.

A juvenile court had been due Monday to hear the case of the girl, Rimsha Masih. But the Islamabad High Court said the hearing should wait until it has ruled on a petition by Rimsha's lawyers seeking a dismissal, one of the lawyers said.

(CNN) - Crowds of angry Muslims attacked Buddhist shrines and homes, torching some of them Sunday in Bangladesh to protest after a photo of a partially burned Quran was posted on Facebook, police said.

The protesters chanted anti-Buddhist slogans, blaming the burning of the Muslim holy book on a Buddhist boy, district police superintendent Saleem Jahangir said.

Islamabad, Pakistan (CNN) - A Pakistani judge on Friday granted bail to Rimsha, a 14-year-old Christian girl detained over accusations she burned pages of the Quran in a case that has heightened religious tensions in the volatile country.

The All Pakistan Minorities Alliance, which represents religious minorities in the country, will pay the sum of roughly $10,000 to secure Rimsha's release from jail, said Tahir Naveed Chaudhry, one of her lawyers and a leading member of the alliance.

(CNN) - An 11-year-old Christian girl has been arrested and detained on charges of blasphemy for allegedly desecrating pages from the Quran in the Pakistan capital Islamabad.

According to a statement released by the President's office on Sunday, the girl, identified as Ramsha, was accused by a local resident of burning pages of the Muslim holy text after she gathered paper as fuel for cooking.

Local media reports said the girl has Down syndrome. CNN was unable to confirm these reports, however Qasim Niazi, the police officer in charge of the police station near where the incident took place, said the girl did not have a mental disorder but was illiterate and had not attended school.

The accused girl had told him she had no idea there were pages of the Quran inside the documents she burnt, he added.

Niazi said that 150 people had gathered on Friday where the neighborhood's Christian population lived and threatened to burn down their houses.

"The mob wanted to burn the girl to give her a lesson," he told CNN.

Other Christian families living in the area have fled fearing a backlash, he added.

The CNN Belief Blog covers the faith angles of the day's biggest stories, from breaking news to politics to entertainment, fostering a global conversation about the role of religion and belief in readers' lives. It's edited by CNN's Daniel Burke with contributions from Eric Marrapodi and CNN's worldwide news gathering team.